Tag: hydrology

What’s happening to Himalayan glaciers, rivers, lakes, and streams has become one of the most important – and widely debated – topics in science.

There’s certainly no shortage of questions. Which of the 15,000 glaciers in the region are retreating and which growing? How many glacial lakes are on the verge of bursting their banks and flooding downstream communities? Will the region’s great rivers, such as the Indus and the Ganges, be able to withstand the region’s changing climate and rapid population growth and continue to sustain the hundreds of millions of people who depend on them? How can devastating floods, such as the one that struck Pakistan last year, be avoided?

Firm answers to such questions have been hard to come by in recent decades because of the limited monitoring resources available in many key countries in the region. Now, however, a new effort, dubbed HIMLA and led by Molly Brown of NASA’s Goddard Space Flight Center, aims to change this by harnessing state-of-the-art, satellite-based monitoring and modeling techniques.

As part of the effort, scientists will feed data from satellite instruments such as MODIS and ASTER into a hydrological model that will produce daily snow/water equivalence maps that will feed into other hydrological models to determine how much freshwater flows into the region’s rivers from snow and glaciers. The ultimate goal: an early warning system that, like the Famine Early Warning System Network does for drought, will help predict floods before they happen.

There’s a staggering amount of science presented every year at the American Geophysical Union meeting, Earth science’s equivalent of the post-season, prom, and a college reunion all rolled into one. This year, with more than 16,000 attendees and 15,815 abstracts on the docket, was no exception.

AGU groups all the abstracts into one of 27 categories. Hydrology garnered the most attention from scientists (12.2 percent of all abstracts) followed closely by Atmospheric Sciences (11.1 percent) and finally Volcanology, Geochemistry, and Petrology (8.0 percent). The full breakdown is below:

One-sixth of the world’s population relies on melted snow for their freshwater, which means good estimates of snow are critical for making realistic predictions of a region’s water supply.

But measuring snow, especially the amount of water locked within that snow, challenges researchers across the globe. Why? The two means of estimating snow totals—weather modeling and satellite remote sensing—can vary as much as 30 percent.

Scientists like hydrologist Edward Kim of NASA’s Goddard Space Flight Center continue to seek ways to reconcile the gap between measurement results. Kim and colleagues Michael Durand (Byrd Polar Research Center), Noah Molotch (Univ. of Colorado), and Steve Margulis (UCLA) are wrapping up a short field campaign to measure snow at the Storm Peak Laboratory, perched atop Colorado’s famed mountain at Steamboat Springs.

Their aim is to test and improve the accuracy of satellite-based snow measurements. In the midst of the expedition, they’ve also snapped some breathtaking photos, such as this sun pillar to the right. Sun pillars are typically caused by sunlight reflecting off the surfaces of falling ice crystals associated with certain cloud types.

This post was adapted from NASA’s Earth Observatory. For more updates on the expedition, please visit the Notes From the Field blog.